Melbourne market terror plot exposed

A plot to bomb Melbourne's Queen Victoria Market, foiled by a British family, never posed any credible terror threat, police say.

The tourist hot spot was on Tuesday revealed as one of multiple targets of a man who claimed to be part of an overseas terrorist network.

Over a five-month period he sent encrypted texts and voice files to members of the family, who acted as willing participants in the scheme, with instructions on how to detonate a bomb at the market, the Herald Sun reported.

But the 'recruit' was actually a family of "amateur jihadi hunters" and the correspondence was forwarded to Australia's Federal and Victorian police.

Assistant Commissioner Ross Guenther on Tuesday said the threat was assessed as not credible and there was no need for concern.

"There is no current threat to the Queen Victoria Market, Federation Square, St Paul's Cathedral or any other location in Melbourne or more broadly, across this state, at this time," he said.

Mr Guenther said early this year, police learned of communications between a person probably in Pakistan and a person in London posing as an extremist.